Since its discovery in 1979, the tumor suppressor p53 has been widely studied and expressed in various organisms, including yeast. Yeast has proven to be a very informative model and an effective system for studying the roles and functions of this protein and gene. This review is a compilation of our team's studies involving p53 expression in yeast. These researches investigated certain aspects, essentially the apoptotic function of p53. Our main contribution to the study and understanding of the p53 gene in the yeast context is the confirmation of a negative effect of p53 on cell growth in both Saccharomyces cerevisiae and Pichia pastoris strains, which ultimately led to apoptotic cell death. This involves a high dose of p53 and the NLS signal, which enables p53 to target both the mitochondria and the nucleus. Prior to that, obtaining the whole protein required a cDNA without its UTR. Thus, a yeast model was developed, allowing verification of p53 activity. Cancer mutants and their revertants could thereby be assessed. This has evolved into a real antioxidant/anti-apoptotic molecular screening mechanism. Two primary applications were achieved: testing the co-expression with the thioredoxin 2 gene (TRX2) and assessing the impact of Nigella sativa seed extracts. Furthermore, the high yield of yeast P53 production allowed its use in serological cancer diagnosis.

Glycosaminoglycans (GAGs) are the carbohydrate portion of proteoglycans (PGS), a family of complex biomacromolecules ubiquitously found in the extracellular matrix and on cell surfaces that play critical roles in a plethora of physiological and pathological processes. In the present work, chondroitin sulfate (CS) and dermatan sulfate (DS) were extracted and purified from the head (GCB) and skin (GDB) of blue runner fish (Caranx crysos) to explore their structural features and biological properties. GCB and GDB were purified by ion-exchange chromatography with yields of 0.82% and 0.61%, respectively. Chemical and structural analysis showed that GCB and GDD demonstrated quite similar sulfation degrees (4.45% and 4.24%, respectively). The molecular weight values obtained for GCB and GDB as estimated by high-performance size exclusion chromatography coupled with a triple detector array (HP-SEC-TDA) were 48.9 and 28.54 KDa, respectively. Structural features were elucidated using FT-IR and 2D NMR spectroscopy. GCB was mainly identified as chondroitin sulfate, containing 82% GlcA and minor proportions of IdoA and IdoA2S (scoring 18% dermatan-like structures). In contrast, GDB was predominantly dermatan sulfate, with a higher unsulfated IdoA content (54%) and a lower GlcA percentage (17%). In vitro anticoagulant activity, evaluated using APTT and PT assays, demonstrated that both GAGs exhibit significant anticoagulant potential. In addition, both fractions exhibited no antiplatelet activity, suggesting that the isolated glycosaminoglycans selectively target the coagulation cascade without affecting platelet aggregation. Furthermore, hemolytic assays confirmed that neither GCB nor GDB showed any hemolytic activity at the tested concentrations. Cytotoxicity assessment in HEK293 and HUVEK cell lines further confirmed the absence of detectable toxicity even at high concentration. Overall, these marine-derived GAGs present promising therapeutic potential as a source of anticoagulant drugs.